Winding for electric machines.



Patented Dec. l0, mm. B. a. LAMME.

WINDING FOR ELECTRICAL MACHINES.

(Application riled Apr. 30, 1001.

(No Modal.)

TOR IIEY.

UNITED STATES PATENT OFFICE.

IISENIAMIN e. LAMME, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR ToWESTINGHOUSE ELECTRIC a MANUFACTURING o, A CORPORA- TION OFPENNSYLVANIA.

WINDING FOR E ECTRICAL MACHINES.

srnoIrIoA'rIoN forming sea of Letters Patent Ne. 688,318, dated December10, 1901.

Application filed A ril 30, 1901.

Serial No. 58,206. (No model.)

To all whom it may concern.-

Be it known that I, BENJAMIN G. LAMME, a citizen of the United States,residing at Pittsburg, in the county of Allegheny and State ofPennsylvania, have invented new and useful Improvements in \Vindings forElectrical Machines, of which the following is a specification.

My invention relates to windings for electrical machines; and it has forits object to provide a winding which shall be suitable for highpotentials by afiording adequate insulation and at the same time economyof space and an advantageous arrangement of conductors.

My invention is primarily designed for the stationary armatures ofhigh-potential polyphase generators; but its use is not necessarilyrestricted to such specific relations.

In the accompanying drawings, Figure 1 isa plan view of a portion of awinding constructed in accordance with my invention. Fig. 2 is a detailview, partially in end elevation and partially in section, of a portionof a slotted core with conductors located in the core-slots. Fig. 3 isan end elevation of that portion of the winding shown in Fig. 1. Fig. tis a detail view of a portion of one set or group of barconductors suchas are employed in connection with my present invention.

In the construction of alternating-current generators of large size anddesigned for. generating currents of high potential it is necessary toso arrange and connect the several elements of the windings that thoseportions between which there is a considerable difference of potentialshall be as widely separated as is consistent with other practicalconsiderations and at the same time be adequately insulated from eachother and from the core.

In order to economize space to as great an extent as possible and at thesame time to avoid danger of short circuits by reason of the breakingdown of insulation, I employ a bar-winding and combine the bars intogroups, so that the bar of each group shall have a minimum diiference ofpotential. .This arrangement enables me to locate the bars of each groupin close proximity to each other and in the same core-slot, and in orderto properly connect the bars, so as to make the windings complete, Ispread the ends of the bars of each group apart, and thus providesufficient space for attaching the end-connectors and at the same timeinsure a sufficient degree of separation for the connectors to provideproper ventilation. Since my presentinvention is not dependent upon anyspecific arrangement of circuits, I have shown only a portion of thewindings, it being understood that the arrangement of the bar-conductorsand end-connectors may be such as to provide a winding for any practicalnumber of phases of current and magnetic poles.

The core 1, to which the windings are to be applied, is provided with asmany slots 2 as there are groups of bars, and these slots are preferablynearly closed,as ind icated in Fig. 2.

The bars 3 are made of dilferent lengths to correspond to thearrangement of end-connectors 4 and to the number of phases of currentto be generated and the ratio between the number of magnetic poles andthe number of core-slots. Each bar 3 is covered with insulation 5, ofsuitable material and thickness,except at its ends,this insulation 5being, however, comparatively thin in order that space may beeconomized, this being permissible by reason of the fact that the barsare so connected in circuit as to provide a minimum difierence ofpotential between those in each group. The number of bars in a groupwill obviously depend upon the arrangement of circuits; but, as hereshown, three bars are arranged side by side and provided with a cell orsheath 6, of suitable material and suitablethickness.Thisheavyinsulating-sheath 6 is of such length as to project beyond theends of the core and may be tapered at its ends, as indicated at 7.

In order that the end-connectors t may be suitably arranged andconnected to appropriate bars 3, the ends of the bars are separated bybending the two outer ones away from the middle bar, as is clearlyindicated in Figs. 1 and 4. The end-connectors are then attached tothese separated ends by means of solder, and, if necessary, also byrivet-s or bolts.

I have shown each end-connector as made of two parallel lengths ofstrap-copper riveted together, the ends being separated, so as toembrace the ends of the bars 3. This particular construction ofend-connectors and the attachment thereof to the conductor-bars m ayobviously be modified, however, if desired.

A winding constructed and arranged as shown and described is Welladapted as regards insulation and ventilation for high-potentialmachines, and while not limited in this respect this particulararrangement would probably be found unnecessary in connection withsmaller machines and relatively low potentials.

I claim as my invention l. A bar-Winding for electrical machines thebars of which are arranged in groups in the core-slots, the bars in eachgroup being spread apart at their ends and connected to other bars ofthe Winding by suitable condoctors.

2. The combination with a slotted core, of a winding comprising aplurality of groups of bars and end-connectors, the bars in the severalgroups being located in close proximity in the core-slots and beingspread apart at their ends for attachment to the connectors.

3. In an electrical machine,the combination with a slotted core, of awinding comprising a set of groups of bars and sets of connectors forthe ends of the bars,the bars of each group being located in closeproximity to each other and being individually and collectivelyinsulated and having their ends spread apart for attachment of theend-connectors.

4. In an electrical machine,the combination with a slotted core, of awinding comprising a set of groups of bars so disposed that there is aminimum difference of potential between bars in the same core-slot, andsets of connectors for the ends of the bars, said ends being spreadapart for attachment of the connectors thereto.

In testimony whereof I have hereunto sub scribed my name this 20th dayof April, 1901.

BENJ. G. LAMHE.

\V itn esses:

WEsLEY G. CARR, BIRNEY IIINEs.

